Toroidal coil



May 13, 1941. K. KOSCHMIEDER TOROIDAL CO IL Filed April 13, 1938impressed upon these Patented May 13, 1941 TOROIDAL COIL KurtKoschmieder,

Falkensee, Germany, asaignor to C. Lorenz Aktiengesellschaft,Berlin-Tempelhof, Lorenzweg, Germany, a company Application April 13,1938, Serial No. 201,702 Germany April 15, 1937 1 Claim (CL 175-359) Theinvention relates to toroidal coils such,

for example, as used for coupling an a transmitter or a measuringreceiver to the energylines of an antenna system freeof fading, such asan Adcock antenna. As is well known, in order to ascertain whether insystems of this kind the energy lines have a radiation or a receptioncomponent, a voltage is by local action lines with the aid of anauxiliary transmitter. The voltage thus added is adjusted to bring aboutan effect counteracting the.so-calledhorizontal effect of the incomingwaves while being of the same magnitude as this.

To such end a coil is placed'around the energy line and fed from a smallhigh frequency generator whose frequency or operating wavelengthcorresponds to that of the direction finding system. The antenna systemis then balanced until high frequency components cease to occur in thedirection finding receiver. If a direction finding transmitter isconcerned instead of a receiver, a measuring receiver is coupled to theenergy lines, and with the aid of this measuring receiver the energylines are balanced to present the minimum radiation. 1

The coil used for coupling either the auxiliary transmitter or themeasuring receiver to the energy lines must be such that it shall notact as a radiating or receiving means. For this reason this coilis'wound in toroidal fashion.

In order that the coil can be qui and simply applied to the energy lineof the antenna system the invention proposes to make it in two parts.Itwillthennotbenecessarytodisconnecttheenergyllneinordertoinsertthecoiltherecver, but the two parts of the cell are simply placed around theline and are then fastened toea'chothen.

Inaccordance with another feature of theinventlontheradiationpropertiesofthecoilare diminished by a screeningprovided on all sides Oneembodimentoftheinventionisdescribed hereafterby way of example, reference being had to the accompanying drawing inwhich Fig. 1 is a partially sectioned side view of a toroidal coil asprovided by the invention, Fig. 2 is a plan view of one half of suchcoil.

The device here shown comprises two half-ring bodies A, B made of asuitable insulating material. Body A carries a toroidal winding Ihofradio cable. Equally, body 13 is fitted with a toroidal radio cablewinding ii. The two wire ends of winding it are joined to a plug 2 each.The plugs 2 areiastened in body A. The two wire ends of winding ii arejoined to a socket I each. The sockets l are fixed in' body B and areadapted to receive the plugs 2. Winding I4 is contained in a screeningjacket 3. Equally, winding ii is provided with a screening 4. Thesejackets are made of strong sheet copper and are subdivided by slots 5, 6in order not to act as short-circuited windings. Fixed to jacket 4 aremetal springs 1 which serve to clot:- trically interconnect the jacketsI, ing the air gap III which there is between the halves of the coil.Jacket 3 has two lugs it while jacket I is provided with two lugs II. Inthese lugs screws 8 are inserted in order is hold the halves of the coiltogether. A screened cable 0, attached to the coil through a screw jointll. serves to connect the coil with the said auxiliary transmitter ormeasuring receiver, as the case may be. These are likewise completelyscreened.

What is claimed is:

A toroidal coil comprising two half-ring shaped insulating bodies, anarcuate solenoidal air-core winding on each or these bodies, asubdivided screening jacket for each of these windings, metal springsfastened to one of such jackets and adapted to engage the other jacket,lugs fitted to the said jackets, fastening screws seated in these lugs,and an arrangement of. plugs and plug said insulating bodies and to thesaid windings are joined.

Jacket

